We report on the electrical and optical characterisation of the high‐permittivity (high‐κ) TiO2 thin films grown by plasma enhanced atomic layer deposition on Si (100) and glass substrates, respectively. TiO2 films were incorporated in metal‐oxide semiconductor (MOS) capacitor structures with an Al metal gate electrode. The as‐deposited films were amorphous; however upon annealing in the temperature range 500–900 °C, crystalline TiO2 in the anatase phase was formed. This was further confirmed by performing Raman measurements where the characteristic features corresponding to the anatase phase were observed. Transmittance and absorption spectra of the as‐deposited and annealed films were performed by UV–Vis measurements showing more than 70% of transmittance. The formation of stoichiometric TiO2 was revealed by X‐ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectroscopy (RBS) analysis performed on annealed samples (500–900 °C). The dielectric constants were calculated from capacitance–voltage (C–V) curves of the MOS structure on the as‐deposited film and annealed films revealing a significant improvement of the dielectric constants from 10 to 75 at AC frequencies of 100 kHz for the 700 °C annealed TiO2 thin films. The increase in the dielectric constant for annealed films could be attributed to the transformation of film structure from amorphous to polycrystalline (anatase). However, the transformation of amorphous to crystalline phase, leads to an increase in the leakage current which was also found best fitted with Schottky emission mechanism at moderated electric fields.

The application of new zirconium precursors for the fabrication of ZrO2 and ZrN thin films by metalorganic chemical vapor deposition (MOCVD) is presented. The all-nitrogen coordinated Zr precursors exhibit improved thermal properties for vapor phase fabrication of thin films. The growth of ZrO2 thin films was realized by the combination of the Zr complex with oxygen, while the formation of ZrN thin films was achieved for the first time employing a single source precursor (SSP) approach. This was enabled by the presence of nitrogen containing ligands which contributes to the formation of the ZrN phase without the need for any additional nitrogen source in contrast to classical film growth processes for ZrN thin films. In the first step the newly developed precursors were evaluated thoroughly for their use in MOCVD applications, and in the next step they were utilized for the growth of ZrO2 and ZrN thin films on Si(100) substrates. Polycrystalline ZrO2 films that crystallized in the monoclinic phase and the fcc-ZrN films oriented in the (200) direction were obtained, and their structure, morphology, and composition were analyzed by a series of techniques. This work shows the potential of tuning precursors for vapor phase fabrication of Zr containing thin films with a goal of obtaining two different classes of material systems (ZrO2 and ZrN) using one common precursor.

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Two different all nitrogen coordinated tungsten complexes, [W(NtBu)2(NMe2)2] (1) and [W(NtBu)2(NMe2){(iPrN)2C(NMe2)}] (2) were compared for metal organic chemical vapour deposition (MOCVD) of tungsten nitride (WN) thin films in a state‐of‐the‐art commercial MOCVD reactor. Precursor performances of both complexes were investigated under single source precursor (SSP) conditions and in the presence of ammonia as reactive gas where WN thin films were deposited on Si (100) substrates in a temperature range of 500–800 °C. The X‐ray diffraction (XRD) analysis showed that the films deposited under SSP conditions contained a mixture of carbide and nitride phases; while upon the addition of ammonia crystalline WN thin films were formed at higher temperatures (T ≥ 600 °C). Elemental composition investigated by complementary techniques such as Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA) and X‐ray photoelectron spectroscopy (XPS) revealed that the films grown in the presence of ammonia had increased levels of nitrogen and a decreased carbon content in comparison to films grown under SSP conditions. WN films deposited in the presence of ammonia show higher resistivity values than those deposited under SSP conditions.

The infrared absorption of hydrogenated silicon nitride (SiNx:H) films provides information about the average configuration of covalent bonds in the film. In plasma enhanced chemical vapor deposited SiNx:H, the absorption spectrum of the NH bonds shows both a systematic shift and a tailing toward lower frequency with the increase in the film density. First-principles computations of NH vibrations show an increased degree of anharmonicity when the H site is weakly interacting with a second neighboring N atom. This interaction becomes more pronounced in films with higher density, which consequently shifts the vibrational spectrum down.